Most currently available neuromodulation techniques for pain work through an open-loop system. The distance between the epidural space and the target of the stimulation in a dynamic body can change because of physiologic conditions. The closed-loop system in spinal cord neuromodulation consists of an integrated system that records real-time electrophysiological activity in the form of evoked compound action potentials and uses it in a feedback mechanism to adjust stimulus output. Wearables represent newly developed technologies that have gained traction in recent years. Their application in pain management is still developing but promising.